This invention relates in general to measurement devices and more particularly to a special purpose calculator in the form of a simulated tractor-trailer vehicle having variable length components for adjusting the tractor wheel base, tractor fifth wheel and trailer king pin settings, trailer length and trailer tandem location to determine that combination of lengths which will meet statutory truck length requirements or the requirements for a particular load.
A particular problem for the purchasers and operators of tractor-trailer vehicles is that the state laws now in effect for governing the length of tractor semi-trailer combinations and weights per axle or per combination of axles on such equipment are inconsistent between the various states of the United States of America. In addition, there are federal laws now in effect for governing the various weight and length combinations for tractor semi-trailers on interstate highways.
In the past, it has been necessary for the purchaser or operator of a tractor-trailer vehicle to perform cumbersome trial and error mathematical calculations to determine optimum lengths for a tractor-trailer vehicle to meet the various statutory requirements. Such calculations required writing paraphernalia and were subject to error especially when performed hastily.
A particular problem with such calculations is to determine the accumulated effect of various tractor-trailer adjustments on the overall vehicle length. For example, the trailer length may be increased by one foot and the trailer king pin location moved rearwardly one foot with no change in the overall vehicle length. It is the difficulty of visualizing and coordinating the various tractor-trailer adjustments which is a constant problem for the owners and operators of tractor-trailer vehicles, particularly those engaged in interstate transportation.